Q: If a harmonium is tempered, how can it be used in Indian Music?

A: For the most part, yes, harmoniums are tempered instruments. This is why they are a bane to purists, and have been banned on All India Radio. Since they are designed to play in different keys, and some people like to play simple chords, they must be tempered. A lot of serious Indian vocalists prefer the harmonium to the sarangi, which is the traditional vocal accompaniment instrument, because of its full rich sound.

Q: Can a harmonium be tuned differently, i.e. non-tempered?

A: Yes. In India, some vocalists (who always use the same SA or tonic) have their harmoniums tuned to match the pure intervals of Indian Music. These instruments can only play in one key. We have tuned harmoniums to different kinds of Just Intonation, and find them to sound very sweet. The downside is that you are limited to one or two keys, and some chords sound awful.